Mongoose填充值并修改对象

const mongoose = require('mongoose');

const userSchema = new mongoose.Schema({
  name: String,
  age: Number,
  // ...
});

const postSchema = new mongoose.Schema({
  title: String,
  content: String,
  author: {
    type: mongoose.Schema.Types.ObjectId,
    ref: 'User'
  },
  // ...
});

const User = mongoose.model('User', userSchema);
const Post = mongoose.model('Post', postSchema);

Post.findOne({ title: 'Some Post' })
  .populate('author')
  .exec((err, post) => {
    if (err) {
      // 处理错误
    } else {
      console.log(post.author.name); // 输出作者的名字
    }
  });